I have a 645 Super which I built/purchased on E bay. So far, has given excellent results. Suggest you download the manual from butkus.com (free manuals, etc.) Regarding the straps, I purchased one on the auction site specifically made for the 645 Super and Pro models. The strap for the earlier series M645 won't fit propertly. By the way, A strap from the RB 67 series will fit the Super/Pro models. I know because I use mine on both. To my knowledge, there isn't a definitive source for info on this save the owners manuals. The camera itself is pretty straight forward and reasonably simple. The lens line is preety wide; I have the 45 f2.8, 80mm f2,8, and 150 f4. The prism meter options are likewise pretty open as well. Good luck with your search.